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      <h3>Explanation of How Threat Rating Summaries Are Calculated</h3>
      
Miradi uses a combination of rules for rolling up ratings across targets and threats, and for the project as a whole.

<p>As shown in the grid below, the bottom row contains the overall ratings for each target, and the far right-hand column contains the ratings for each threat. Finally, the cell in the lower right-hand corner contains the overall rating for the project. Normally the overall project rating is based on rolling up the threat ratings in the right-most column, using the 3-5-7 and 2-Prime rules.</p>

<h4>3-5-7 Rule</h4>
Multiple threats to individual targets and multiple target threat scores are first summed together using the 3-5-7 rule:
      
<ul>
<li>3 High rated threats are equivalent to 1 Very High-rated threat;</li>
<li>5 Medium rated threats are equivalent to 1 High-rated threat;</li>
<li>7 Low rated threats are equivalent to 1 Medium-rated threat</li>
</ul>

<p>
In the example below, the second row shows the Housing threat. There are 3 High ratings (which equals 1 Very High) and 1 Very High rating, so it is treated as if it had two Very High ratings. In the Ione Chapparal Column, there are 5 Medium ratings (which equals one High), plus one High, for a total equivalent of 2 High ratings.</p>
 
<h4>2-Prime Rule</h4>
After the 3-5-7 rule has been applied, the 2-prime rule is used to determine the rolled up rating for a target, a threat, or for the whole project. This rule requires the equivalent of two ratings at a certain level for the end result to be that level. For example, there would have to be the equivalent of at least two Very High ratings to produce a Very High result, or two ratings of Medium or above to produce a Medium result.
      
<p>In the example below, the Housing threat row has the equivalent of two Very High ratings (due to the 3-5-7 rule), so the result is Very High. The Recreational Vehicles row has one Medium rating and one Low. Since it does not have two or more Mediums, the result is Low.</p>

<h4>Majority Override</h4>      
The Majority Override rule ensures that the overall project rating is not reduced too much by the other rules. Normally, the overall project rating is a rollup of the threat ratings, using the rules above. However, if a majority of the targets have a rating higher than that computed rollup, then that majority rating is used instead.</p>

<p>For example, if the result of using the 3-5-7 and 2-prime rules gave a project rating of Medium, but 4 out of the 6 targets had at least one rating of at High (or Very High), then the Majority Override rule would take effect and the overall project rating would be High.</p>

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      <img width="834" height="350" src="images/BundleSummaries.png">
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